1. Technical Field
The present invention relates to the field of voice processing and, more particularly, to text-to-speech applications.
2. Description of the Related Art
Text-to-speech (TTS) applications can be used in a variety of different environments and settings with each environment having an associated level of background noise or ambient noise. The louder the ambient noise within a particular environment, the louder the speech generated by a TTS application needs to be in order for a user to intelligibly comprehend the speech.
Conventional TTS applications provide a user-adjustable volume mechanism for controlling the volume of the output of generated speech. Such a control mechanism can provide a fixed output level for the TTS application. When the ambient noise levels change, however, the user of the TTS application can be forced to either correspondingly manually adjust the volume of the output level or to listen to a signal that is relatively too soft or too loud. When the output level is too soft, the generated speech can be difficult to understand or can be completely unintelligible. When the output level is too loud, the volume level can be uncomfortable for the user and disturbing to inadvertent peripheral listeners within close proximity to the user of the TTS application.
The output level of TTS applications can be excessively problematic in environments with varying ambient noise levels. For example, a TTS application within an automobile, such as a TTS application disposed within a vehicle navigation system, can experience many different ambient noise levels during normal usage. For instance, the appropriate output level for the TTS application can be vastly different when the automobile is at a stop than when the automobile is moving at high speed. Similarly, a comfortable output level can vary substantially when a window of the automobile is up verses down or when surrounding traffic is light verses heavy. As devices that utilize TTS applications proliferate and become more integrated within portable computing devices, the aforementioned difficulties will likely worsen.